LabWindows question

[MikaelH]

Hi Guys

Sorry for using such a bad word as LabWindows here on LAVA, but I have a development team in Fremont and Shanghai that develop all their code in LabWindows. Since you can't do all cool stuff there I had to write the intelligent code in LabVIEW, and have them to call my LV exe file.

I let them control the behaviour to my exe file with arguments so they can call it like this: MES_Finish.exe --PreCure or MES_Finish.exe –PostCure

But the developers say that LabWindows can't call exe files with arguments.

Does anybody know if this is true?

A work around that didn't work either, was for them to call 2 batch files with the argument syntax in.

Cheers,

Mike

[asbo]

I haven't used LabWindows, so I can't answer your first question, but I don't understand why the batch file wouldn't work...

[MikaelH]

It could be that the devlopers are senior enough...

[candidus]

Here is a quote from the CVi documentation:

LaunchExecutable

int LaunchExecutable (char filename[]);

Purpose

Starts running a program and returns without waiting for the program to exit.

Note If you want to wait for the program to exit, use the system function in the ANSI C Library.

The program must be an actual executable; that is, you cannot launch commands intrinsic to a command interpreter.

The executable can be either a DOS or Windows executable, including *.exe, *.com, *.bat, and *.pif files.

.exe, .com, and .bat DOS programs use the settings in _default.pif (in the Windows directory) when running. You can change their priority, display options, and so on., by editing _default.pif or by creating another .pif file. Refer to www.msdn.com for information about creating and editing .pif files.

If you need to execute a command built into command.com such as copy, dir, and others, you can call LaunchExecutable with the following command:

command.com /C DosCommand args

where DosCommand is the shell command you want to execute. For example, the following command string copies file.tmp from the temp directory to the tmp directory:

command.com /C copy c:\\temp\\file.tmp c:\\tmp

Note If you want to monitor whether the launched executable has terminated, use LaunchExecutableEx.

In other words: It should work...

[viSci]

Could you compile your LV code to a DLL?

[asbo]

In other words: It should work...

Sounds like the LW developers are full or malarkey, then...

[MikaelH]

Thanks, so maybe this command would work: command.com /C Myexefile.exe -- arguments

And why not, I can create a DLL also...or convince them to migrate to a real programing language ;-)

[candidus]

It definitely works. I played around with the different LW API functions. You can even use the system() function that is part of the ANSI C library. My example command was:

char *cmd="cmd /k echo \"Hello world\"";

Here are the options:

// Does not wait for the executable to finish.

LaunchExecutable(cmd);

// Waits for the executable to finish. Even part of the ANSI C standard.

system(cmd);

// Runs the executable...

int procHandle = 0;

LaunchExecutableEx(cmd, LE_SHOWNORMAL, &procHandle);

// .. and enters a loop (timing 0.1s) that waits for the executable to finish.

while(!ExecutableHasTerminated(procHandle))

{

Delay(0.1);

}

There's really no problem here, perhaps there was one years ago in the stone age of programming, I have no clue :-)

And why not, I can create a DLL also...or convince them to migrate to a real programing language ;-)

That may be an even better idea ;-)

[MikaelH]

Thank you